Purification of sphalerite concentrate in the chemical and flotation way
In this paper the results of the investigation of magnesium removal, from zinc concentrate derived from zinc-lead ore enrichment plant, have been presented. The characteristics of the initial concentrate and the occurrence forms of dolomite in this material are estimated. It was found that magnesium is collected in the finest fraction of the initial material. The influence of chemical treatment and flotation on the quality improvement of zinc concentrate is determined. This method permits to obtain zinc concentrate containing below 0,3% Mg and about 0,7% Ca.
This research emphasizes eloquently on membrane technology for treatment of palm oil mill effluent (POME) as it is the Malaysia’s largest and most important agro based industry. Findings established significant quality improvement with an efficient recovery of water from palm oil mill via innovative membrane application. Conventional bio-methods, whilst adhering to the Department of Environment’s (DOE) discharge regulations, produces brownish liquid which pales in comparison to the crystal clear water obtained through membrane treatment. The pre-treatment process consists of coagulation-flocculation using green environmental coagulant bases such as Moringa oleifera (MO) seeds. The ultrafiltration polyvinylidene difluoride (PVDF) and thin film composite (TFC) reverse osmosis were vital for the membrane processes. The system gave 99% suspended solids reduction in suspended solid and 78% of water present was successfully recovered. This technology guarantees water recovery with drinking water quality; meeting the US Environmental Protection Agency (USEPA) standard or could be recycled into the plant with sludge utilization for palm oil estates, thus enabling the concept of zero discharge to be executed in the industries. In addition, green and healthy antioxidants such as oil and beta-carotene can be recovered from POME further demonstrate. Silica gel showed better performance in separation of carotenes from oil at temperature 40°C using adsorption chromatography with 1154.55 ppm. The attractiveness of this technology, enabling the utilization of reuse of agricultural waste into potentially value added products.
In the last 50 years, both the authorities and the majority of the citizens have understood the need to enforce measures to both preserve energy and reduce the costs of producing it. Nowadays, every developed country has correlated the profitability and the competitiveness of its industry with the efficient and sustainable use of energy and is therefore making conscious efforts to improve these areas. Any action program deemed to enhance energy efficiency has as main component the critical analysis of the energetic resources allocated to an activity in a given perimeter, also known as energy audit. This paper aims to develop a model of risk classification to be applied in planning and performing procedures during energy audit, which can allow a common framework to be developed in this area of audit. The stakeholders of the entity will also be offered a unitary perspective regarding the risks of the respective business, which can be helpful in their decision-making process. The research methodology of this paper consists of quantitative instruments, namely the statistical analysis of a database containing energy audit conclusions of companies in Europe. The indicators used will relate to energy savings, the number of measures implemented as a result of the audit, the percentage of energy saved from total consumption (energy efficiency) and the business line of the company. The novelty this framework will bring consists of the congruence created in the energy audit procedures of different practices and of the standardization and quality improvement in energy audit opinions. The approach of energy audits will therefore evolve towards a risk based one, rather than an analytical one. Also, we will explain the importance of energy savings for the profitability and the competitiveness of companies in the economy today, while facilitating a transparent communication with the stakeholders. This analysis is relevant especially given the fact that the cycle of 4 years after the directive of mandatory energy audit has been enforced ends with 2018 and a conclusion can be drawn before the new audit period starts in 2019.
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Katarína Hroboňová, Andrea Špačková and Martina Ondáková
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